There is an ongoing demand in the aerospace and industrial industry for low cost electromagnetic coil assemblies suitable for usage in coiled-wire devices, such as actuators (e.g., solenoids) and sensors (e.g., variable differential transformers), capable of providing prolonged and reliable operation in high temperature environments characterized by temperatures exceeding 260° C. and, preferably, in high temperature environments characterized by temperatures approaching or exceeding 400° C. In general, an electromagnetic coil assembly includes at least one magnet wire, which is wound around a bobbin or similar support structure to produce at least one multi-turn coil. When designed for usage within a solenoid, the electromagnetic coil assembly often includes a single coil; while, when utilized within a variable differential transformer, the electromagnetic coil assembly typically includes a primary coil and two or more secondary coils. To provide mechanical isolation, position holding, and electrical insulation between neighboring turns, the wire coil or coils may be potted in a body of insulative material (referred to herein as an “electrically-insulative body”). The opposing ends of the wire coil or coils are fed through the electrically-insulative body for electrical connection to, for example, feedthroughs mounted through the device housing. In the case of a conventional, non-high temperature electromagnetic coil assembly, the insulative body is commonly formed from a plastic or other readily-available organic dielectric material. Organic materials, however, rapidly decompose, become brittle, and ultimately fail when subjected to temperatures exceeding approximately 260° C.; and are consequently unsuitable for usage within high temperature electromagnetic coil assemblies of the type described above. Organic insulative materials also tend to be relatively sensitive to radiation and are consequently less well-suited for usage within the nuclear industry.
Considering the above, it would be desirable to provide embodiments of an electromagnetic coil assembly for usage within coiled-wire devices (e.g., solenoids, variable differential transformers, and two position sensors, to list but a few) suitable for operating in high temperature environments characterized by temperatures exceeding 260° C. and, preferably, approaching or exceeding approximately 400° C. Ideally, embodiments of such an electromagnet coil assembly would be relatively insensitive to radiation and well-suited for usage within nuclear applications. It would also be desirable to provide embodiments of a method for manufacture such a high temperature electromagnetic coil assembly. Other desirable features and characteristics of the present invention will become apparent from the subsequent Detailed Description and the appended claims, taken in conjunction with the accompanying Drawings and the foregoing Background.